Compositions of volatile organic compounds and methods of use thereof

ABSTRACT

The present invention provides compositions and methods for treating, inhibiting or preventing the developing of a plant pathogenic disease. The compositions comprise volatile organic compounds effective to inhibit the growth of, or kill pathogenic microbes, including  Ganoderma boninense . Invention compositions are especially useful in preventing and treating basal stem rot in the oil palm, and can be applied in the vicinity of the plant or used to sterilize the plant growth medium prior to or concurrent with plant growth therein.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 12/753,714 filed Apr. 2, 2010, now issued as U.S. Pat. No.8,425,946; which claims the benefit under 35 U.S.C. §119(e) to U.S.Application Ser. No. 61/230,672 filed Jul. 31, 2009 and to U.S.Application Ser. No. 61/166,684 filed on Apr. 3, 2009. The disclosure ofeach of the prior applications is considered part of and is incorporatedby reference in the disclosure of this application including all tables,figures and claims.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to compositions of volatile organiccompounds with biological activity against plant pathogens, particularlythe fungus Ganoderma boninense that is a causative agent of the oil palmdisease Ganoderma Basal Stem Rot. The disclosure also providescompositions comprising at least one known pesticidal agent useful forselective pest control applications.

2. Background Information

Oil palm, Elaeis guineensis, is the most important plantation crop inMalaysia. Four tons of palm oil are produced annually per hectare fromthis crop plant. Many small private landowners are able to profit fromthe production and sale of the palm oil, making this an activity ofgreat economic importance. Presently, Malaysia's oil palm industry isunder threat as it is faced with a very serious plant disease problem.This problem is a prevailing incurable oil palm disease called GanodermaBasal Stem Rot (BSR) caused by Ganoderma boninense. Presently, BSR israpidly becoming the major threat to oil palm cultivation and palm oilproduction in Southeast Asia.

In BSR disease, basal stem rot is only one part of the disease cycle.Ganoderma boninense also causes a seedling disease and an upper stem rotof more developed palms. Spores of G. boninense have multiple roles inthe infection process to bring about the three distinct phases of thisimportant plant disease. This pathogenic organism is also prevalent onother major plantation plants including coconut, betel nut, tea, cacao,acacia and poplar.

With no effective cure at present, BSR has a huge economic impact on theMalaysian oil palm industry. Thus, plant health is crucial in obtainingmaximal productivity of the oil palm and techniques, methods andmanagement ideas are needed to control BSR. Attempts to control thisdisease with agrochemicals have not been very successful. This could bedue to the fact that the oil palms already possessed latent fungalinfections at the time of the chemical treatment. Biological controlagents have also been tried against Ganoderma with limited success.Saprophytic organisms (such as Trichoderma harzianum) merely arrest thespread of disease by competing against Ganoderma to reduce itsopportunity to colonize oil palm roots.

BSR is a particular concern because the activity of replanting oil palmscan accelerate spread of the disease. It is well known that successivereplanting of oil palms can be rapidly exploited by soil borne fungisuch as Ganoderma. Soils that continuously support the growth of palmseventually act as a reservoir for Ganoderma fruiting structures andspores of this organism. Soils that are replanted with new palms areimmediately exposed to a high load of inoculum (spores) and eventuallybecome infected by Ganoderma boninense.

It is widely believed that the problem of basal stem rot of palm willbecome increasingly serious as more and more established plantationsbecome due for second or even third replanting. Environmentalconsiderations, coupled with governmental directives, will reduceexploitation of new forest areas, making further replanting of thesecrops necessary. There is a need for integrated management systems forGanoderma and related diseases to maintain the success of the oil palmindustry.

SUMMARY OF THE INVENTION

The compositions of the present invention may be used to control majordiseases of plants caused by a variety of plant pathogens. One exemplaryplant is the oil palm, whereby compounds may inhibit or prevent thedevelopment of basal stem rot disease. These compounds may targetGanoderma boninense, a causative agent of basal stem rot disease.

One aspect of the invention provides a composition for treating,inhibiting or preventing at least one plant pathogenic disease. Thecomposition comprises two or more compounds wherein at least one of thecompounds is isobutyric acid, methyl isobutyrate or isobutyricanhydride. The second compound of the composition is selected fromisobutyric acid, methyl isobutyrate, isobutyric anhydride, ethylisobutyrate, propyl isobutyrate, isobutyric acid-allyl ester,naphthalene, caryophyllene, and a plant essential oil. The compositionmay also be a combination of three or more of these compounds, or mayfurther include additional components, including volatile organiccompounds (VOCs). Additional compounds may include, but are not limitedto, one or more of naphthalene or naphthalene derivatives,caryophyllene, isocaryophyllene, α-humulene, and the compounds providedin Table 1 herein; compounds produced by Muscodor species, such as thevolatile organic compounds listed in Table 2 herein; and plant essentialoils, such as those listed in Table 3 herein.

In some preferred embodiments, the composition includes 20-70%isobutyric acid, 20-70% methyl isobutyrate, 20-70% isobutyric anhydride,or any combination thereof. In further embodiments, this compositionfurther comprises 1-10% naphthalene, caryophyllene, or a plant essentialoil. In certain preferred embodiments, the composition comprises 42-53%isobutyric acid, 42-53% methyl isobutyrate, and 3-7% naphthalene,caryophyllene, or a plant essential oil. In other preferred embodiments,the composition includes 42-53% isobutyric acid, 42-53% isobutyricanhydride, and 3-7% naphthalene, caryophyllene, or a plant essentialoil.

In other preferred embodiments, the composition further comprises anagriculturally effective amount of a pesticidal compound or composition.The additional compound or composition may be an acaricide, abactericide, a fungicide, an insecticide, a microbicide, a nematicide,or a food preservative.

The composition in some embodiments may be in the form of a powder, agranule, a pellet, a gel, an aqueous suspension, a solution or anemulsion. The composition may be provided with a carrier, such as anagriculturally acceptable carrier. The carrier can be a seed.

Another aspect of the invention provides a method for treating,inhibiting or preventing the development of a plant pathogenic disease,comprising applying a composition of the invention in the vicinity ofthe plant. In a preferred embodiment, the pathogen may be Aspergillusfumigatus, Botrytis cinerea, Cerpospora betae, Curvularia sp., Ganodermaboninense, Geotrichum candidum, Mycosphaerella fijiensis, Phytophthorapalmivora, Phytophthora ramorum, Pythium ultimum, Rhizoctonia solani,Rhizopus sp., Schizophyllum sp., Sclerotinia sclerotiorum, Verticilliumdahliae, or Xanthomonas axonopodis. In another preferred embodiment, thehost plant is susceptible to disease caused by Ganoderma boninense. Inanother preferred embodiment, the host plant is an oil palm plant. Incertain embodiments, the method is effective to inhibit the growth ofthe plant pathogen. In preferred embodiments, the method is effective tokill the plant pathogen.

Some embodiments provide for the composition to be applied to thevicinity or a plant, such as around the roots, stems, trunk, seed, orleaves of the plant, applied onto such parts of the plant, or injectedinto such parts of the plant. In other embodiments, the composition canbe used to treat or sterilize the soil or plant growth medium, byexposing the soil or plant growth medium to vapors from the inventioncomposition, or by direct contact, such as intermixing, with thecomposition.

Another aspect of the invention provides a method for screeningmicrobial strains that may be useful for treating, inhibiting orpreventing the development of a plant pathogenic disease. The methodcomprises (i) exposing or contacting candidate microbial strains with aninvention composition, (ii) selecting microbial strains resistant to thecomposition, and (iii) characterizing the selected microbial strain. Theinvention also includes the microbial strains obtained from the methodas described above.

Another aspect of the invention relates to a method for killing,inhibiting or preventing the development of an undesired organism, suchas a fungus, a bacterium, a microorganism, a nematode, and an insect.The method comprises exposing or contacting the organism to or with aneffective amount of an invention composition.

These and other objects and features of the invention will become morefully apparent when the following detailed description of the inventionis read in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts the effect of treating soil with a composition of theinvention. Treated soil on the right shows no growth of microorganismson soil inoculated with Ganoderma boninense; while the untreated controlplate on the left shows extensive growth.

DETAILED DESCRIPTION OF THE INVENTION Definitions

Unless otherwise defined, all terms of art, notations and otherscientific terms or terminology used herein are intended to have themeanings commonly understood by those of skill in the art to which thisinvention pertains. In some cases, terms with commonly understoodmeanings are defined herein for clarity and/or for ready reference; andthe inclusion of such definitions herein should not necessarily beconstrued to represent a substantial difference over what is generallyunderstood in the art. Many of the techniques and procedures describedor referenced herein are well understood and commonly employed usingconventional methodology by those skilled in the art.

The singular form “a”, “an”, and “the” include plural references unlessthe context clearly dictates otherwise. For example, the term “a cell”includes one or more cells, including mixtures thereof.

Bactericidal: The term “bactericidal”, as used herein, refers to theability of a substance to increase mortality or inhibit the growth rateof bacteria.

Biological Control: As used herein, “biological control” is defined ascontrol of a pathogen or insect or any other undesirable organism by theuse of a second organism. An example of a known mechanism of biologicalcontrol is the use of enteric bacteria that control root rot byout-competing fungi for space on the surface of the root. Bacterialtoxins, such as antibiotics, have been used to control pathogens. Thetoxin can be isolated and applied directly to the plant or the bacterialspecies may be administered so it produces the toxin in situ.

Culturing: The term “culturing”, as used herein, refers to thepropagation of organisms on or in media of various kinds.

Composition: A “composition” is intended to mean a combination of activeagent and another compound, carrier or composition, inert (for example,a detectable agent or label or liquid carrier) or active, such as apesticide.

Derivative: As used herein, a “derivative” of a chemical compound is acompound that can be chemically or biologically derived from theoriginal compound, for example by the addition, substitution or deletionof chemical components of the original compound. For example, aderivative may be an isomer of the referenced compound, an anhydride ofthe referenced compound, or has one or more chemical groups added orsubstituted with respect to the referenced compound. For example,propanoic acid, 2-methyl, 3-methylbutyl ester is considered to be aderivative of propanoic acid.

Effective Amount: An “effective amount”, as used herein, is an amountsufficient to affect beneficial or desired results. An effective amountcan be administered in one or more administrations. In terms oftreatment, inhibition or protection, an effective amount is that amountsufficient to ameliorate, stabilize, reverse, slow or delay progressionof the target infection or disease states.

Fungicidal: As used herein, “fungicidal” refers to the ability of asubstance to decrease the rate of growth of fungi or to increase themortality of fungi.

Fungus: The term “fungus” or “fungi”, as used herein, includes a widevariety of nucleated spore-bearing organisms that are devoid ofchlorophyll. Examples of fungi include yeasts, molds, mildews, rusts,and mushrooms.

Insecticidal: As used herein, ‘Insecticidal’ refers to the ability of asubstance to increase mortality or inhibit the growth rate of insects ortheir larvae.

Microbicidal: “Microbicidal”, as used herein, refers to the ability of asubstance to increase mortality or inhibit the growth rate ofmicroorganism.

Mutant: As used herein, the term “mutant” or “variant” refers to amodification of the parental strain in which the desired biologicalactivity remains similar to that of the parental strain. Mutants orvariants may occur in nature without the intervention of man. They alsoare obtainable by treatment with or by a variety of methods andcompositions known to those of skill in the art. For example, parentalstrains may be treated with a chemical such asN-methyl-N′-nitro-N-nitrosoguanidine, ethylmethanesulfone, or byirradiation using gamma, x-ray, or UV-irradiation, or by other meanswell known to those practiced in the art.

Nematicidal: The term “nematicidal”, as used herein, refers to theability of a substance to increase mortality or inhibit the growth rateof nematodes.

Plant Oil: A “plant oil”, “plant essential oil”, or “plant volatileoil”, as used herein, is any oil derived from any part of a plant, andincludes any compound purified or derived from a plant oil, such as ahydrophobic, volatile organic compound that is produced by a plantspecies. An exemplary plant essential oil is caryophyllene, a naturalbicyclic sesquiterpene that is a constituent of many plant essentialoils, such as oils obtained from cannabis (Cannabis sativa), hemp,marijuana, caraway (Carum carvi), cloves (Syzygium aromaticum), hops(Humulus lupulus), basil (Ocimum), oregano (Origanum vulgare), pepper(Piper nigrum), rosemary (Rosmarinus oficinalis), cinnamon (Cimmamomunzeylanicum or tamala). A plant essential oil used in a composition asdisclosed herein need not be isolated from a plant, for example, it maybe chemically synthesized or isolated from a microorganism that producesthe compound. Exemplary plant essential oils are provided in Table 3herein.

Pesticidal: The term “pesticidal”, as used herein, refers to the abilityof a substance to decrease the rate of growth of a pest, i.e., anundersired organism, or to increase the mortality of a pest.

Volatile: “Volatile compounds” and “volatile organic compounds” (VOCs),as used herein, are compounds that in most instances evaporate readilyat ambient temperature and pressure. Volatile compounds of the presentinvention must be present “in the vicinity” of the target pathogenicorganism for effectiveness. The invention compositions are thus placedin the vicinity of the host plant or the target organism, or in thegrowth medium or soil of the host plant prior to or concurrent withplant growth. Generally, volatile compounds are in the vicinity of thetarget pathogenic organism so long as they achieve their biologicaleffect prior to evaporation. They may be spread on or around the base ofthe host plant or intermixed with the growth medium or soil of theplant. Physical contact with the host plant or target pathogen is notrequired due to the dispersal of the volatiles through the air or soil.

The discussion of the general methods given herein is intended forillustrative purposes only. Other alternative methods and embodimentswill be apparent to those of skill in the art upon review of thisdisclosure.

Compositions of Volatile Organic Compounds

The invention provides compositions of volatile organic compounds thatcan be used to treat or prevent growth of a pathogen, such as but notlimited to a plant pathogen. Table 1 provides exemplary compounds thatcan be used in compositions and methods of the present invention. Table2 herein provides the VOCs produced by a fourteen day old culture ofMuscodor strobelii. M. strobelii producing these compounds wasdemonstrated to be lethal to several species of pathogenicmicroorganisms including Aspergillus fumigatus, Botrytis cinerea,Cerpospora betae, Curvularia sp., Ganoderma boninense, Geotrichumcandidum, Mycosphaerella fijiensis, Phytophthora palmivora, Phytophthoraramorum, Pythium ultimum, Rhizoctonia solani, Rhizopus sp.,Schizophyllum sp., Sclerotinia sclerotiorum, Verticillium dahliae, andXanthomonas axonopodis.

TABLE 1 Compounds of the Present Invention Compound IUPAC Name CASRegistry # MW ethanol ethanol 64-17-5 46 acetone propanone 67-64-1 582-butanone butan-2-one 78-93-3 72 methyl acetate methyl acetate 79-20-974 isobutyl alcohol 2-methylpropan-1-ol 78-83-1 74 isobutyric acid2-methyl propanoic acid 79-31-2 88 ethyl acetate ethyl acetate 141-78-688 N,2-dimethylpropanamide 2675-88-9 101 isobutyric acid, methyl estermethyl-2-methylpropanoate 547-63-7 102 (methyl isobutyrate)1-(ethenyloxy)-3-methyl-butane 39782-38-2 114 octane octane 111-65-9 114methyl 2-methoxypropenoate 17639-76-8 116 butyl acetate butyl ethanoate123-86-4 116 isobutyl acetate isobutyl acetate 110-19-0 116 isobutyricacid, ethyl ester ethyl-2-methylpropanoate 97-62-1 116 (ethylisobutyrate) phenethyl alcohol 2-phenylethanol 60-12-8 122 allyl2-methylpropanoate 15727-77-2 128 naphthalene naphthalene 91-20-3 128methyl 2,3-dimethylbutanoate 30540-29-5 130 isobutyric acid, propylester propyl-2 methylpropanoate 644-49-5 130 (propyl isobutyrate)3-methyl-1-butanol 3-methyl-1-butanol 123-51-3 131 2-nonanone heptylmethyl ketone 821-55-6 142 2-methylheptanoic acid 1188-02-9 144 aceticacid, (tert-butylthio)- 24310-22-3 148 pentamethyl-benzene 700-12-9 1482-(1-Propenyl)-6-methylphenol 148 undecane undecane 1120-21-4 156isobutyric anhydride 2-methylpropanoyl 2-methyl propanoate 97-72-3 1584,4-diethyl-2,5-octadiyne 61227-87-0 162 butyl propyl oxalate 26404-30-8188 4,5-dimethyl-1,2,3,6,7,8,8a,8b- 188 octahydrobiphenylene4,5-dehydro-isolongifolene 202 alpha-gurjunene 489-40-7 204(−)-arstolene 25274-27-5 204 alpha-patchoulene 560-32-7 204(−)-tricyclo[6.2.1.0(4,11)]undec-5- 204 ene,1,5,9,9-tetramethyl-(isocaryophyllene-II) bergamotene 6895-56-3 204(Z)-7,11-dimethyl-3-methylene- 204 1,6,10-dodecatriene caryophyllene4,11,11-trimethyl-8-methylene- 87-44-5 204 bicyclo[7.2.0]undec-4-eneheptyl allyl oxalate 228 isoamyl isobutyrate 3-methylbutyl2-methylpropanoate 2050-01-3 316

In some embodiments of the invention, a composition used to inhibit orprevent development of a plant pathogenic disease, or infestation by aplant pathogen comprises at least 20 percent, at least 25 percent, atleast 30 percent, at least 35 percent, at least 40 percent, at least 45percent, at least 50 percent, at least 55 percent, at least 60 percent,at least 65 percent or at least 70 percent isobutyric acid, methylisobutyrate or isobutyric anhydride. A preferred range is 20-70%,30-60%, or 40-50%, and a most preferred range is 42-53%.

In some embodiments, a composition of the invention further includes, asa second compound, at least 20 percent, at least 25 percent, at least 30percent, at least 35 percent, at least 40 percent, at least 45 percent,at least 50 percent, at least 55 percent, at least 60 percent, at least65 percent, or at least 70 percent isobutyric acid, methyl isobutyrate,isobutyric anhydride, ethyl isobutyrate, propyl isobutyrate, isobutyricacid-allyl ester. A preferred range is 20-70%, 30-60%, or 40-50%, and amost preferred range is 42-53%.

In some embodiments, a composition of the invention further includes, asa second or third compound, at least 1 percent, at least 2 percent, atleast 3 percent, at least 4 percent, at least 5 percent, at least 6percent, at least 7 percent, at least 8 percent, at least 9 percent orat least 10 percent of naphthalene, caryophyllene or a plant essentialoil. A preferred range is 1-10%, 2-9%, or 3-8%, and a most preferredrange is 3-7%.

A composition of the invention can include one or more additionalcompounds, which can be any compounds that do not negatively affect theability of the composition to inhibit the growth of or kill one or morepathogenic microorganisms, where a pathogenic microorganism can be amicroorganism that causes disease in a plant or an animal. In someexamples, a composition of the invention includes one or more VOCs inaddition to isobutyric acid, methyl isobutyrate, or isobutyricanhydride. For example, the composition can include additional VOCsproduced by M. strobelii or other fungi, including other Muscodorspecies. A composition may also be a combination of three or more ofthese compounds, or may further include additional components, includingvolatile organic compounds (VOCs) and plant essential oils. Additionalcompounds may include, but are not limited to, one or more ofnaphthalene or naphthalene derivatives, caryophyllene, isocaryophyllene,α-humulene, and the compounds provided in Table 1 herein; compoundsproduced by Muscodor species, such as the volatile organic compoundslisted in Table 2 herein; and plant essential oils, such as those listedin Table 3 herein.

For example, Muscodor albus produces, among other VOCs, octane, acetone,ethanol, isobutyl alcohol, methyl acetate, ethyl acetate, various methylesters of propanoic acid, butanol derivatives, furan, nonanonederivatives, naphthalene, azulene, cyclohexene and caryophyllene (U.S.Pat. No. 6,911,338, incorporated herein by reference). Muscodorvitigenus produces, for example, naphthalene and naphthalenederivatives, among other VOCs (U.S. Pat. No. 7,267,975, incorporatedherein by reference). VOCs identified as produced by M. strobelii areprovided herein in Table 2. Volatile compounds produced by M. albus, M.vitigenus, or M. strobelii can be used in a composition of theinvention, in addition to derivatives of these compounds.

Other compounds that can be included in a composition of the inventioninclude plant essential oils. Plant essential oils can include volatilehydrocarbon compounds obtained from any part of a plant, including theleaves, stems, roots, seeds, bark, wood, fruit (including rinds), orflowers of plant, or any oil derived from any plant parts. Includedwithout limitation are oils extracted or derived from Mentha arvensis,Eucalyptus, Lisea cubea, peppermint, spearmint, wintergreen, clove,lemon, grapefruit, lime, tangerine, and orange, as well as oilsextracted or derived from allspice or juniper berries, from anise,celery, or cumin seeds, or from almonds or nutmeg, and any constituentsor derivatives thereof. Also included are oils extracted or derived frombasil, bay, cinnamon, sage, lemon grass, Melaleuca, oregano, rosemary,patchouli, pine, cannabis, chamomile, sage, clove, geranium, hops,hyssop, jasmine, lavender, manuka, marjoram, camphor, rosewood,cedarwood, sandalwood, agarwood, ginger, galangal, tea tree, bergamot,and valerian, and any constituents or derivatives thereof. Table 3provides some examples of plant essential oils that can be used incompositions of the invention.

An exemplary composition of the invention is a mixture of isobutyricacid, methyl isobutyrate, and naphthalene. For example, compositions maycomprise 20-70% isobutyric acid, 20-70% methyl isobutyrate, and 1-10%naphthalene. In some embodiments, the composition comprises 30-60%isobutyric acid. In some embodiments, the composition comprises 30-60%methyl isobutyrate. In some embodiments, the composition comprises42-53% isobutyric acid, 42-53% methyl isobutyrate, and 3-7% naphthalene.For example, the composition can comprises 47.5% isobutyric acid, 47.5%methyl isobutyrate, and 5% naphthalene.

Another exemplary composition is a mixture of isobutyric acid,isobutyric anhydride, and naphthalene. For example, compositions maycomprise 20-70% isobutyric acid, 20-70% isobutyric anhydride, and 1-10%naphthalene. In some embodiments, the composition comprises 30-60%isobutyric acid. In some embodiments, the composition comprises 30-60%isobutyric anhydride. In some embodiments, the composition comprises42-53% isobutyric acid, 42-53% isobutyric anhydride, and 3-7%naphthalene. For example, the composition can comprise 47.5% isobutyricacid, 47.5% isobutyric anhydride, and 5% naphthalene.

Other examples of compositions of the invention include mixtures ofisobutyric acid, an isobutyric acid derivative, and one or more plantessential oil, which can be any plant essential oil, including but notlimited to plant essential oils as provided in Table 3. In someembodiments, a plant essential oil used in a composition of theinvention is caryophyllene or a derivative of caryophyllene, such asisocaryophyllene or α-humulene. For example, in some embodiments, acomposition includes 20-70% isobutyric acid, 20-70% methyl isobutyrateor isobutyric anhydride, and 1-10% of a plant essential oil.

One exemplary composition is a mixture of isobutyric acid, methylisobutyrate, and caryophyllene. For example, compositions may comprise20-70% isobutyric acid, 20-70% methyl isobutyrate, and 1-10%caryophyllene. In some embodiments, the composition comprises 30-60%isobutyric acid. In some embodiments, the composition comprises 30-60%methyl isobutyrate. In some embodiments, the composition comprises42-53% isobutyric acid, 42-53% methyl isobutyrate, and 3-7%caryophyllene. For example, the composition can comprises 47.5%isobutyric acid, 47.5% methyl isobutyrate, and 5% caryophyllene.

Yet another exemplary composition is a mixture of isobutyric acid,isobutyric anhydride, and caryophyllene. For example, compositions maycomprise 20-70% isobutyric acid, 20-70% isobutyric anhydride, and 1-10%caryophyllene. In some embodiments, the composition comprises 30-60%isobutyric acid. In some embodiments, the composition comprises 30-60%isobutyric anhydride. In some embodiments, the composition comprises42-53% isobutyric acid, 42-53% isobutyric anhydride, and 3-7%caryophyllene. For example, the composition can comprise 47.5%isobutyric acid, 47.5% isobutyric anhydride, and 5% caryophyllene.

In yet other embodiments, the composition can include, in addition toisobutyric acid and, optionally a derivative thereof, one or moresesquiterpenes, such as the sesquiterpenes present in the VOCs of M.strobelii. A sesquiterpene used in a composition of the invention can bea pheromone, such as a pheromone that affects the behavior of one ormore insect species. For example, sesquiterpene compounds such asisocaryophyllene or derivatives thereof (e.g.,(−)-tricyclo[6.2.1.0(4,11)]undec-5-ene,1,5,9,9-tetramethyl-(isocaryophyllene-II),bergamotene or derivatives thereof, patchoulene or derivatives thereof(e.g., alpha-patchoulene), gurjunene or derivatives thereof (e.g.,alpha-gurjunene), aristolene or derivatives thereof (e.g.,(−)-aristolene, or isolongifolene or derivatives thereof (e.g.,4,5-dehydro-isolongifolene) present individually at molar percentages of10 percent or less in the mixture of VOC s produced by a Muscodor straincan be present in a composition of the invention.

The disclosure provides compositions of compounds and optionally acarrier. The carrier may be any one or more of a number of carriers thatconfer a variety of properties, such as increased stability,wettability, dispersability, etc. Suitable formulations that may beprepared include wettable powders, granules, pellets, gels,microencapsulated particles, and the like, liquids such as aqueousflowables, aqueous suspensions, etc. The carrier may be an agriculturalcarrier. In certain embodiments the carrier is a seed, and thecomposition may be applied or coated onto the seed or allowed tosaturate the seed.

The agricultural carrier may be soil or plant growth medium. Otheragricultural carriers that may be used include water, fertilizers,plant-based oils, humectants, or combinations thereof. The compositioncan be provided as a solution that is injected or intermixed into thesoil. The composition can be formulated as a particle or granule havinga coating that dissolves over time or on wetting to release the volatilecomposition.

Alternatively, the agricultural carrier may be a solid, such asdiatomaceous earth, alginate, clay, other plant and animal products, orcombinations, including granules or suspensions. For example, theaqueous suspension, solution, or emulsion may be provided with a carrierto facilitate dispersal of the composition through the soil. Materialssuch as vermiculite, peat, natural or man-made fibers, or biologicalmaterial such as seed, plant parts, empty fruit bunches (EFBs) frompalm, sugar cane bagasse, hulls or stalks from grain processing, groundplant material (“yard waste”) or wood from building site refuse, sawdustor small fibers from recycling of paper, fabric, or wood can be soakedin the composition, and then mixed with the soil or growth medium usedfor planting a plant species of interest. The agricultural carrier, soilor plant growth medium need not be in direct contact with thecomposition, for example, it can be treated or sterilized by vapors fromthe composition in the vicinity.

When used as pesticides or fungicide in their commercially availableformulations and in the use forms prepared with these formulations, theactive compounds according to the invention can furthermore be presentin the form of a mixture with synergists. Synergists are compounds bywhich the activity of the active compounds is increased without it beingnecessary for the synergist added to be active itself.

When used as pesticides in their commercially available formulations andin the use forms prepared with these formulations, the active compoundsaccording to the invention can furthermore be present in the form of amixture with inhibitors which reduce the degradation of the activecompound after application in the habitat of the plant, on the surfaceof parts of plants or in plant tissues.

The active compounds according to the invention, as such or in theirformulations, can also be used as a mixture with known acaricides,bactericides, fungicides, insecticides, microbicides, or nematicides, orcombinations thereof, for example in order to widen the spectrum ofaction or to prevent the development of resistances in this way. In manycases, synergistic effects result, i.e. the activity of the mixture canexceed the activity of the individual components. A mixture with otherknown active compounds, such as fertilizers, growth regulators, safenersand/or semiochemicals is also possible.

In a preferred embodiment of the present invention, the composition mayinclude at least one of a biological and an additional chemicalpesticide. Exemplary chemical pesticides include those in theorganophosphate, carbamate, organochlorine, and prethroid classes. Alsoincluded are chemical control agents such as, but not limited to,benomyl, borax, captafol, captan, chorothalonil, formulations containingcopper; formulations containing zinc; dichlone; dicloran; iodine;fungicides that inhibit ergosterol biosynthesis such as but not limitedto fenarimol, imazalil, myclobutanil, propiconazole, prochloraz,terbutrazole, flusilazole, triadimefon, and tebuconazole; folpetipordione; manocozeb; maneb; metalaxyl; oxycarboxin, oxytetracycline;PCNB; pentachlorophenol; quinomethionate; sodium aresenite; sodium DNOC;sodium hypochlorite; sodium phenylphenate; streptomycin; sulfur;thiabendazolel; thiophanate-methyl; triforine; vinclozolin; zineb;ziram; tricyclazole; cymoxanil; blastididin; and validimycin.

Exemplary biological pesticides include microbes, animals, plants,bacteria, genetic material, and natural products of living organisms.For example, fungi that can be combined with a composition that includesisobutyric acid, methyl isobutyrate, or isobutyric anhydride, include,without limitation, Muscodor species, Fusarium lateritium, Metarhiziumanisopliae (“green muscarine”), Metarhizium flaviride, Beauveriabassiana (“white muscarine”), Beauveria brongniartii, Chladosporiumherbarum, Paecilomyces farinosus, Paecilomyces fitmosoroseus,Verticillium lecanii, Hirsutella citriformis, Hirsutella thompsoni,Aschersonia aleyrodis, Entomophaga grylli, Entomophaga maimaiga,Entomophaga muscae, Entomophaga praxibulli, Entomophthora plutellae,Zoophthora radicans, Neozygitesfloridana, Nomuraea rileyi, Pandoraneoaphidis, Tolypocladium cylindrosporum, Culicinomyces clavosporus,Muscodor albus, Cordyceps variabilis, Cordyceps facis, Cordycepssubsessilis, Cordyceps myrmecophila, Cordyceps sphecocephala, Cordycepsentomorrhiza, Cordyceps gracilis, Cordyceps militaris, Cordycepswashingtonensis, Cordyceps melolanthae, Cordyceps ravenelii, Cordycepsunilateralis, Cordyceps sinensis and Cordyceps clavulata, andmycorrhizal species such as Laccaria bicolor. Other mycopesticidalspecies will be apparent to those skilled in the art.

Exemplary food preservatives include antimicrobial preservatives, whichinhibit the growth of bacteria and fungi and mold growth, orantioxidants such as oxygen absorbers, which inhibit the oxidation offood constituents. Common antimicrobial preservatives include calciumpropionate, sodium nitrate, sodium nitrite, sulfites (sulfur dioxide,sodium bisulfite, potassium hydrogen sulfite, etc.) and disodium EDTA.Antioxidants include BHA and BHT. Other preservatives includeformaldehyde (usually in solution), glutaraldehyde (kills insects),ethanol and methylchloroisothiazolinone.

Using methods well known to those of skill in the art, the volatileorganic compounds may also be used to treating or protecting non-plantmaterials from fungal or toxic mold infestations. For example, thevolatile compounds may be used to treat or prevent toxic mold onbuilding materials and in buildings by contacting the building, thebuilding materials, or the spaces between the building materials with aneffective amount of the volatile composition. Further, an effectiveamount of the volatile compounds can be used alone or in combinationwith other fumigants in a room or alternatively, during whole buildingfumigations.

Treating Plant Pathogens Volatile Organic Compounds

The invention further provides a method for treating, inhibiting, orpreventing the development of a plant pathogen disease comprisingapplying a composition of the invention to a plant, or in the vicinityof the plant prior to or concurrent with plant growth. The plant treatedaccording to the methods of the invention can be any type of plant,including trees, crop plants, and ornamental plants of any species.Where the composition is applied to the soil or a growth medium, thesoil or medium can support the growth of any type of plant. For example,a composition of the invention can be applied to an oil palm (Elaeisguineensis), coconut (Cocos nucifera), betel (Areca catechu), tea(Camellia sinensis), cocoa (Theobroma cacao), acacia (Acacia species),or poplar (Populus species) plant, or soil or a growth medium thatsupports growth of any of these or other plant species.

The composition can be any disclosed herein. In some preferredembodiments, the composition comprises isobutyric acid, methylisobutyrate, and naphthalene. In some embodiments, the compositioncomprises 20-70% isobutyric acid, 20-70% methylisobutyrate, and 1-10%naphthalene. In some exemplary embodiments, the composition comprises42-53% isobutyric acid, 42-53% methylisobutyrate, and 3-7% naphthalene.

In other preferred embodiments, the composition comprises isobutyricacid, isobutyric anhydride, and caryophyllene. In some embodiments, thecomposition comprises 20-70% isobutyric acid, 20-70% isobutyricanhydride, and 1-10% caryophyllene. In some exemplary embodiments, thecomposition comprises 42-53% isobutyric acid, 42-53% isobutyricanhydride, and 3-7% caryophyllene.

The composition can include carriers or other compounds that aid inapplication of the compounds to the plant, and/or adherence of thecompound to the plant or vicinity of the plant. For example, thecomposition can be in the form of an emulsion, such as a water-in-oilemulsion, or can be provided with one or more surfactants, such as anionic or nonionic surfactant. The composition of volatile organiccompounds can be provided with a carrier such as particles or powder.Other exemplary carriers include soil, the agricultural and absorbentcarriers listed below, and seeds, branches, mulch, and plant fragmentsthat can be spread at the base of the plant. Carriers also includecompounds known to those of skill in the art that reduce the volatilityof the volatile organic compounds during storage, shipment, and planttreatment. Such carriers may be desirable to affect a controlled releaseof the volatile organic compounds during plant treatment.

In some embodiments, the composition is a liquid composition, and may bean emulsion, and the composition is used to wipe, water, spray, ordrench the plant or areas of the plant, such as the roots. Plants, orparts of plants such as the roots, can in some embodiments be dunkedinto the composition or wrapped in a fabric, fibers, or a filter ormatrix that contains or is saturated with the composition prior toplanting or transplanting. In some embodiments, the composition isinjected into a plant, for example, into the roots, trunk, stems, orleaves. In some embodiments, the volatile organic compound compositionis watered into the soil.

A seed coating or seed dressing formulation can be applied to the seedsemploying the compositions of the invention and a diluent in suitableseed coating formulation form, e.g., as an aqueous suspension or in adry powder form having good adherence to the seeds. Such seed coating orseed dressing formulations are known in the art. Such formulations maycontain the single active ingredients or the combination of activeingredients in encapsulated form, e.g., as slow release capsules ormicrocapsules.

The composition may be topically administered to plants, including anyor all plant parts, including without limitation, roots, shoots, stems,bark, leaves, fruit, and/or seeds. For example, the volatile compoundcomposition may be applied on, in, or near the root of the oil palm.Single and multiple applications are contemplated. Multiple applicationscan be through more than one application method.

The compositions of the invention are particularly useful in combatingplant pests and plant pathogens, particularly phytopathogenic fungi.Thus, the invention has may be used to treat, inhibit or prevent thedevelopment of plant pathogenic diseases caused by a broad range offungi. The compositions and methods of the present invention arepreferably used against fungi that are important or interesting foragriculture, horticulture, plant biomass for the production of biofuelmolecules and other chemicals, and/or forestry. Non-limiting examplesinclude, for instance, Acremonium strictum, Agrobacterium tumefaciens,Alternaria alternata, Alternaria solani, Aphanomyces euteiches,Aspergillus fumigatus, Athelia rolfsii, Aureobasidium pullulans,Bipolaris zeicola, Botrytis cinerea, Calonectria kyotensis,Cephalosporium maydis, Cercospora medicaginis, Cercospora sojina,Colletotrichum coccodes, Colletotrichum fragariae, Colletotrichumgraminicola, Coniella diplodiella, Coprinopsis psychromorbida,Corynespora cassiicola, Curvularia pallescens, Cylindrocladiumcrotalariae, Diplocarpon earlianum, Diplodia gossyina, Diplodia spp.,Epicoccum nigrum, Erysiphe cichoracearum, Fusarium graminearum, Fusariumoxysporum, Fusarium oxysporum f.sp. tuberosi, Fusarium proliferatum var.proliferatum, Fusarium solani, Fusarium verticillioides, Ganodermaboninense, Geotrichum candidum, Glomerella tucumanensis, Guignardiabidwellii, Kabatiella zeae, Leptosphaerulina briosiana, Leptotrochilamedicaginis, Macrophomina, Macrophomina phaseolina, Magnaporthe grisea,Magnaporthe oryzae, Microsphaera manshurica, Monilinia fructicola,Mycosphaerella fijiensis, Mycosphaerella fragariae, Nigrospora oryzae,Ophiostoma ulmi, Pectobacterium carotovorum, Pellicularia sasakii(Rhizoctonia solani), Peronospora manshurica, Phakopsora pachyrhizi,Phoma foveata, Phoma medicaginis, Phomopsis longicolla, Phytophthoracinnamomi, Phytophthora erythroseptica, Phytophthora fragariae,Phytophthora infestans, Phytophthora medicaginis, Phytophthoramegasperma, Phytophthora palmivora, Podosphaera leucotricha,Pseudopeziza medicaginis, Puccinia graminis subsp. Tritici (UG99),Puccinia sorghi, Pyricularia grisea, Pyricularia oryzae, Pythiumultimum, Rhizoctonia solani, Rhizoctonia zeae, Rosellinia sp.,Sclerotinia sclerotiorum, Sclerotinina trifoliorum, Sclerotium rolfsii,Septoria glycines, Septoria lycopersici, Setomelanomma turcica,Sphaerotheca macularis, Spongospora subterranea, Stemphylium sp,Synchytrium endobioticum, Thecaphora (Angiosorus), Thielaviopsis,Tilletia indica, Trichoderma viride, Ustilago maydis, Verticilliumalbo-atrum, Verticillium dahliae, Verticillium dahliae, Xanthomonasaxonopodis, Xanthomonas oryzae pv. oryzae.

In a preferred embodiment of the present invention, the application ofthe volatile compound composition to the plant results in a reducedoccurrence of at least one plant disease caused by a bacterium, fungus,or insect as compared with plants not treated with the composition. Insome embodiments, the plant disease is caused by Aspergillus fumigatus,Botrytis cinerea, Cerpospora betae, Curvularia spp., Ganodermaboninense, Geotrichum candidum, Mycosphaerella fijiensis, Phytophthorapalmivora, Phytophthora ramorum, Pythium ultimum, Rhizoctonia solani,Rhizopus spp., Schizophyllum spp., Sclerotinia sclerotiorum,Verticillium dahliae, or Xanthomonas axonopodis. In a particularlypreferred embodiment of the invention, the host plant is susceptible todiseases caused by Ganoderma boninense. In another preferred embodiment,the host plant is an oil palm plant. In other preferred embodiments, thedisclosed compositions and methods are effective to kill the plantpathogen.

It is understood that all plants and plant parts can be treated inaccordance with the invention. Plants are to be understood as meaning inthe present context all plants and plant populations such as desired andundesired wild plants or crop plants (including naturally occurring cropplants). Crop plants can be plants which can be obtained by conventionalplant breeding and optimization methods or by biotechnological andrecombinant methods or by combinations of these methods, including thetransgenic plants and plant cultivars protectable or not protectable byplant breeders' rights. Plant parts are to be understood as meaning allparts and organs of plants above and below the ground, such as shoot,leaf, flower and root, examples which may be mentioned being leaves,needles, stalks, stems, flowers, fruit bodies, fruits, seeds, roots,tubers and rhizomes. The plant parts also include harvested material,and vegetative and generative propagation material, for examplecuttings, tubers, rhizomes, offsets and seeds.

As discussed above, the compositions and methods according to thepresent invention in principle can be applied to any plant. Therefore,monocotyledonous as well as dicotyledonous plant species areparticularly suitable. The process is preferably used with plants thatare important or interesting for agriculture, horticulture, for theproduction of biomass used in producing liquid fuel molecules and otherchemicals, and/or forestry.

Thus, the invention has use over a broad range of plants, preferablyhigher plants pertaining to the classes of Angiospermae andGymnospermae. Plants of the subclasses of the Dicotylodenae and theMonocotyledonae are particularly suitable. Dicotyledonous plants belongto the orders of the Magniolales, Illiciales, Laurales, PiperalesAristochiales, Nymphaeales, Ranunculales, Papeverales, Sarraceniaceae,Trochodendrales, Hamamelidales, Eucomiales, Leitneriales, Myricales,Fagales, Casuarinales, Caryophyllales, Batales, Polygonales,Plumbaginales, Dilleniales, Theales, Malvales, Urticales, Lecythidales,Violales, Salicales, Capparales, Ericales, Diapensales, Ebenales,Primulales, Rosales, Fabales, Podostemales, Haloragales, Myrtales,Cornales, Proteales, Santales, Raffiesiales, Celastrales, Euphorbiales,Rhamnales, Sapindales, Juglandales, Geraniales, Polygalales, Umbellales,Gentianales, Polemoniales, Lamiales, Plantaginales, Scrophulariales,Campanulales, Rubiales, Dipsacales, and Asterales. Monocotyledonousplants belong to the orders of the Alismatales, Hydrocharitales,Najadales, Triuridales, Commelinales, Eriocaulales, Restionales, Poales,Juncales, Cyperales, Typhales, Bromeliales, Zingiberales, Arecales,Cyclanthales, Pandanales, Arales, Lilliales, and Orchidales. Plantsbelonging to the class of the Gymnospermae are Pinales, Ginkgoales,Cycadales and Gnetales.

Suitable species may include members of the genus Abelmoschus, Abies,Acer, Agrostis, Allium, Alstroemeria, Ananas, Andrographis, Andropogon,Artemisia, Arundo, Atropa, Berberis, Beta, Bixa, Brassica, Calendula,Camellia, Camptotheca, Cannabis, Capsicum, Carthamus, Catharanthus,Cephalotaxus, Chrysanthemum, Cinchona, Citrullus, Coffea, Colchicum,Coleus, Cucumis, Cucurbita, Cynodon, Datura, Dianthus, Digitalis,Dioscorea, Elaeis, Ephedra, Erianthus, Erythroxylum, Eucalyptus,Festuca, Fragaria, Galanthus, Glycine, Gossypium, Helianthus, Hevea,Hordeum, Hyoscyamus, Jatropha, Lactuca, Linum, Lolium, Lupinus,Lycopersicon, Lycopodium, Manihot, Medicago, Mentha, Miscanthus, Musa,Nicotiana, Oryza, Panicum, Papaver, Parthenium, Pennisetum, Petunia,Phalaris, Phleum, Pinus, Poa, Poinsettia, Populus, Rauwolfia, Ricinus,Rosa, Saccharum, Salix, Sanguinaria, Scopolia, Secale, Solanum, Sorghum,Spartina, Spinacea, Tanacetum, Taxus, Theobroma, Triticosecale,Triticum, Uniola, Veratrum, Vinca, Vitis, and Zea.

The methods of the present invention are preferably used in plants thatare important or interesting for agriculture, horticulture, biomass forthe production of biofuel molecules and other chemicals, and/orforestry. Non-limiting examples include, for instance, Panicum virgatum(switchgrass), Sorghum bicolor (sorghum, sudangrass), Miscanthusgiganteus (miscanthus), Saccharum sp. (energycane), Populus balsamifera(poplar), Zea mays (corn), Glycine max (soybean), Brassica napus(canola), Triticum aestivum (wheat), Gossypium hirsutum (cotton), Oryzasativa (rice), Helianthus annuus (sunflower), Medicago sativa (alfalfa),Beta vulgaris (sugarbeet), Pennisetum glaucum (pearl millet), Panicumspp., Sorghum spp., Miscanthus spp., Saccharum spp., Erianthus spp.,Populus spp., Andropogon gerardii (big bluestem), Pennisetum purpureum(elephant grass), Phalaris arundinacea (reed canarygrass), Cynodondactylon (bermudagrass), Festuca arundinacea (tall fescue), Spartinapectinata (prairie cord-grass), Arundo donax (giant reed), Secalecereale (rye), Salix spp. (willow), Eucalyptus spp. (eucalyptus),Triticosecale spp. (triticum—wheat X rye), Bamboo, Carthamus tinctorius(safflower), Jatropha curcas (Jatropha), Ricinus communis (castor),Elaeis guineensis (oil palm), Phoenix dactylifera (date palm),Archontophoenix cunninghamiana (king palm), Syagrus romanzoffiana (queenpalm), Linum usitatissimum (flax), Brassica juncea, Manihot esculenta(cassaya), Lycopersicon esculentum (tomato), Lactuca saliva (lettuce),Musa paradisiaca (banana), Solanum tuberosum (potato), Brassica oleracea(broccoli, cauliflower, brusselsprouts), Camellia sinensis (tea),Fragaria ananassa (strawberry), Theobroma cacao (cocoa), Coffea arabica(coffee), Vitis vinifera (grape), Ananas comosus (pineapple), Capsicumannum (hot & sweet pepper), Allium cepa (onion), Cucumis melo (melon),Cucumis sativus (cucumber), Cucurbita maxima (squash), Cucurbitamoschata (squash), Spinacea oleracea (spinach), Citrullus lanatus(watermelon), Abelmoschus esculentus (okra), Solanum melongena(eggplant), Papaver somniferum (opium poppy), Papaver orientate, Taxusbaccata, Taxus brevifolia, Artemisia annua, Cannabis saliva, Camptothecaacuminate, Catharanthus roseus, Vinca rosea, Cinchona officinalis,Coichicum autumnale, Veratrum califormica, Digitalis lanata, Digitalispurpurea, Dioscorea spp., Andrographis paniculata, Atropa belladonna,Datura stomonium, Berberis spp., Cephalotaxus spp., Ephedra sinica,Ephedra spp., Erythroxylum coca, Galanthus wornorii, Scopolia spp.,Lycopodium serratum (Huperzia serrata), Lycopodium spp., Rauwolfiaserpentine, Rauwolfia spp., Sanguinaria canadensis, Hyoscyamus spp.,Calendula officinalis, Chrysanthemum parthenium, Coleus forskohlii,Tanacetum parthenium, Parthenium argentatum (guayule), Hevea spp.(rubber), Mentha spicata (mint), Mentha piperita (mint), Bixa orellana,Alstroemeria spp., Rosa spp. (rose), Dianthus caryophyllus (carnation),Petunia spp. (petunia), Poinsettia pulcherrima (poinsettia), Nicotianatabacum (tobacco), Lupinus albus (lupin), Uniola paniculata (oats),bentgrass (Agrostis spp.), Populus tremuloides (aspen), Pinus spp.(pine), Abies spp. (fir), Acer spp. (maple), Hordeum vulgare (barley),Poa pratensis (bluegrass), Lolium spp. (ryegrass), Phleum pratense(timothy), and conifers. Of interest are plants grown for energyproduction, so called energy crops, such as cellulose-based energy cropslike Panicum virgatum (switchgrass), Sorghum bicolor (sorghum,sudangrass), Miscanthus giganteus (miscanthus), Saccharum sp.(energycane), Populus balsamifera (poplar), Andropogon gerardii (bigbluestem), Pennisetum purpureum (elephant grass), Phalaris arundinacea(reed canarygrass), Cynodon dactylon (bermudagrass), Festuca arundinacea(tall fescue), Spartina pectinata (prairie cord-grass), Medicago sativa(alfalfa), Arundo donax (giant reed), Secale cereale (rye), Salix spp.(willow), Eucalyptus spp. (eucalyptus), Triticosecale spp.(triticum—wheat X rye), and Bamboo; and starch-based energy crops likeZea mays (corn) and Manihot esculenta (cassaya); and sucrose-basedenergy crops like Saccharum sp. (sugarcane) and Beta vulgaris(sugarbeet); and biofuel-producing energy crops like Glycine max(soybean), Brassica napus (canola), Helianthus annuus (sunflower),Carthamus tinctorius (safflower), Jatropha curcas (Jatropha), Ricinuscommunis (castor), Elaeis guineensis (African oil palm), Elaeis oleifera(American oil palm), Cocos nucifera (coconut), Camelina sativa (wildflax), Pongamia pinnata (Pongam), Olea europaea (olive), Linumusitatissimum (flax), Crambe abyssinica (Abyssinian-kale), and Brassicajuncea.

Treatment of Soil with Volatile Organic Compounds

The invention provides for a method to treat soil or other similar plantgrowth media with compositions of the present invention. The inventionprovides a method to use compositions as disclosed herein to kill plantpathogens in soil. Typically, the composition comprises two or morevolatile organic compounds and, optionally, an agricultural carrier.Carriers in some embodiments reduce loss of the volatile organiccompounds during application. In some embodiments, the carriers areabsorbent materials that can be soaked in or permeated with thecomposition, such that the absorbent material can hold and preventimmediate volatilization and diffusion of the compounds of thecomposition. Once mixed with the soil, the carrier can allow moregradual release of the volatile compounds through the soil. Examples ofsuch carriers include, without limitation, peat, humus, vermiculite,shredded paper, paper, fabric, or wood fibers from waste or recyclingprocesses, sawdust, ground of pulverized sugar bagasse, grain husks, orempty fruit bunches, etc. Other agricultural carriers include seeds,branches, mulch, plant fragments, and powdered milk. One agriculturalcarrier is soil itself. The soil or plant growth media may be treatedprior to (e.g., a sterilization treatment before planting) or concurrentwith plant growth (e.g., a treatment while planting, or after growth isestablished).

The volatile organic compounds are added to the soil. Mixing may then beperformed to distribute the compounds throughout the vicinity of thetarget plant pathogen. In other embodiments, the volatile compoundcomposition is mixed directly with the soil in the absence of a solid orparticulate carrier.

In yet other embodiments; the composition is injected into the soil. Forexample, a composition that includes isobutyric acid, methylisobutyrate, or butyric anhydride can be provided in a vessel underpressure, and can be injected about one, two, three, four, five, six,seven, eight, nine, ten, between ten and fifteen, or between fifteen andtwenty centimeters, between twenty and thirty centimeters, betweenthirty and fifty centimeters, or further below the surface of the soilat intervals throughout an area that is planted with a plant species ofinterest, or will be planted with a plant species of interest. In someembodiments, the soil is covered after injection of the composition toreduce loss of the volatile compound. For example, plastic sheeting canbe used to cover the injected area so that it remains covered for fromabout eight hours to about one month after injection.

The treated soil may be then used for planting of plants susceptible topathogens that can be effectively inhibited or killed by the volatileorganic compounds. In some embodiments, soil or plant growth medium istreated where plants have already been planted or established in thesoil or growth medium. Volatile organic compounds may also be topicallyadministered to plants, including all plant parts, specifically on, in,or near the roots of the oil palm. In some embodiments, soil may betreated while plants are growing in the soil.

In yet other embodiments, a compound of the invention is watered intothe soil from an irrigation system, for example, a spray or dripirrigation system.

The composition with soil or an agricultural carrier may also be appliedto the base of oil palm plants. The composition may also be directlyapplied to the roots of the plants. The plants may have root diseasecaused by a plant pathogen. The plant pathogen may be Ganodermaboninense. Other exemplary plant pathogens causing root diseases includePhytophthora palmivora, Pythium ultimum, or Sclerotinia sclerotiorum. Itis desired that the volatile organic compounds inhibit growth of or killplant pathogenic fungi such as Ganoderma boninense, Phytophthorapalmivora, Pythium ultimum, and Sclerotinia sclerotiorum.

Another aspect of the invention provides a method for screeningmicrobial strains that may be useful for treating, inhibiting orpreventing the development of a plant pathogenic disease. The methodinvolves (i) exposing or contacting candidate microbial strains with theinvention composition, (ii) selecting microbial strains resistant to thecomposition, and (iii) characterizing the selected microbial strain. Thecharacterization of the selected microbial strains can be carried by avariety of known molecular and microscopy techniques. Non-limitingexamples of such techniques include electron microscopy, GC-MS analysisof VOC profile, PCR amplification and phylogenetic analysis of the 18Sor the ITS-5.8S rDNA sequences.

The discussion of the general methods given herein is intended forillustrative purposes only. Other alternative methods and embodimentswill be apparent to those skilled in the art upon review of thisdisclosure. The following examples are offered to illustrate, but notlimit, the invention.

Example 1 Quantitative Analysis of Volatile Organic Compounds (Vocs)from Muscodor strobelii

The gases in the air space above a 14 day old culture of the MB-8Muscodor strobelii growing on a Petri plate (PDA) were quantitativelyanalyzed (live culture deposited on Jun. 5, 2009 in the AgriculturalResearch Culture Collection located at 1815 N. University Street,Peoria, Ill. 61604, USA (NRRL) in accordance with the Budapest Treaty onthe International Recognition of the Deposit of Microorganisms for thePurpose of patent Procedure and the Regulations thereunder (BudapestTreaty) as Accession Number NRRL 50288). First, a baked “Solid PhaseMicro Extraction” syringe (Supelco) consisting of 50/30divinylbenzene/carburen on polydimethylsiloxane on a stable flex fiberwas placed through a small hole drilled in the side of the Petri platesporting the growth of MB8. The fiber was exposed to the vapor phase ofthe fungus for 45 minutes. The syringe was then inserted into thesplitless injection port of a Hewlett Packard 6890 gas chromatographcontaining a 30 m×0.25 mm I.D. ZB Wax capillary column with a filmthickness of 0.50 mm. The column was temperature programmed as follows:30° C. for 2 minutes followed to 220° C. at 5° C./minute. The carriergas was ultra high purity Helium (local distributor), and the initialcolumn head pressure was 50 kPa. Prior to trapping the volatiles, thefiber was conditioned at 240° C. for 20 minutes under a flow of heliumgas. A 30 second injection time was used to introduce the sample fiberinto the GC. The gas chromatograph was interfaced to a Hewlett Packard5973 mass selective detector (mass spectrometer) operating at unitresolution. Data acquisition and data processing were performed on theHewlett Packard ChemStation software system. Initial identification ofthe unknowns produced by MB8 was made through library comparison usingthe NIST database. The identified compounds and their peak areas areprovided in Table 2.

TABLE 2 VOCs Produced by a 14 Day Old Culture of Muscodor strobelii onPDA. Retention Peak Time Area Possible Compound MW 3.853 6.07 Acetone 584.287 2.28 2-Butanone 72 4.887 33.13 Isobutyric acid, methyl ester 1025.682 122.88 Isobutyric acid 88 5.740 3.77 Methyl 2-methoxypropenoate116 5.903 2.29 Acetic acid, (tert-butylthio)- 148 6.389 2.862-Methylheptanoic acid 144 6.504 0.35 Methyl 2,3-dimethylbutanoate 1306.961 11.04 Allyl 2-methylpropanoate 128 (isobutyric anhydride) 7.5121.13 N,2-dimethylpropanamide 101 9.090 0.39 Heptyl allyl oxalate 2289.931 0.26 Butyl propyl oxalate 188 10.012 0.221-(ethenyloxy)-3-methyl-butane 114 11.278 2.94 alpha-Gurjunene 20411.332 2.15 (−)-Aristolene 204 11.436 1.07 alpha-Patchoulene 204 11.5576.28 4,5-dimethyl-1,2,3,6,7,8,8a,8b- 188 octahydrobiphenylene 11.74014.91 (−)-tricyclo[6.2.1.0(4,11)]undec-5- 204ene,1,5,9,9-tetramethyl-(isocaryophyllene-II) 11.929 0.44pentamethyl-benzene 148 12.032 0.74 Bergamotene 204 12.099 0.144,4-diethyl-2,5-octadiyne 162 12.190 0.34 2-(1-Propenyl)-6-methylphenol148 12.446 0.06 (Z)-7,11-dimethyl-3-methylene-1,6,10- 204 dodecatriene12.683 0.86 4,5-dehydro-isolongifolene 202

Example 2 Use of Compositions of Volatile Organic Compounds to KillPlant Pathogens

A composition containing a mixture of volatile compounds was prepared asfollows: 47.5% isobutyric acid, 47.5% methyl ester of isobutyric acid(methyl isobutyrate), and 5% naphthalene.

To test the bioactivity, the mixture was placed in a small cup in thecenter of a Petri plate with potato dextrose agar (PDA) (Strobel et al.,2001 Microbiology 147: 2943-2950). The volumes of liquid tested were 0,2.5, 5.0, 10.0 and 20 microliters as per Strobel et al., supra. Thensmall cubes of fungal inoculum grown on PDA were also applied to theplate. The plates were sealed with parafilm and incubated for 3 days, atwhich time measurements of hyphal development were made. Also, after 3days the small plug of fungal inoculum was removed from the plate andtransferred to a fresh PDA plate to determine if the test fungus wasstill alive (capable of growth) and this was recorded. The resultsshowed that Ganoderma boninense and Pythium ultimum and Phytophthorapalmivora were each killed by the lethal mixture of volatile compounds.

In another experiment, a composition containing a mixture of volatilecompounds that included caryophyllene was tested for its ability toinhibit the growth of fungal pathogens. Caryophyllene is a sesquiterpeneVOC that is found in products of certain plants, for example, essentialoils such as clove oil. Additional examples of plant essential oils thatcan be present in a composition of the invention are provided in Table3.

TABLE 3 Exemplary Plant Essential Oils basil oil black pepper oil(±)-camphor carvacrol trans-cinnamaldehyde cinnamon leaf oil cinnamonbark oil citronellol citral (±)-citronellal clove bud oil eucalyptoleucalyptus oil eugenol fennel oil geraniol ginger oil jojoba oillemongrass oil limonene linalool patchouli oil peppermint oilα-terpinene rosemary oil tea tree oil thyme oil

A mixture of 47.5% isobutyric acid; 47.5% isobutyric anhydride; and 5%caryophyllene was placed in a small cup in the center of a Petri platewith potato dextrose agar (PDA) and tested for activity on fungal asdescribed above. The results showed that Ganoderma boninense and Pythiumultimum and Phytophthora palmivora were also each killed by this mixtureof volatile compounds.

To determine the effectiveness of individual components of the testedVOC mixtures in killing pathogenic fungi, isobutyric acid and methylisobutyrate were also tested on their own. In one experiment, isobutyricacid was placed in a small cup in the center of a Petri plate withpotato dextrose agar (PDA) and tested for activity on fungi as describedabove. The results showed that the growth of each of Ganoderma boninenseand Pythium ultimum and Phytophthora palmivora was inhibited byisobutyric acid alone, but not killed even at the higher concentrations.

In another experiment, the methyl ester of isobutyric acid (methylisobutyrate) was placed in a small cup in the center of a Petri platewith potato dextrose agar (PDA) and tested for activity on fungi asdescribed above. The results showed no growth inhibition of Ganodermaboninense and Pythium ultimum or Phytophthora palmivora occurred withmethyl isobutyrate alone, even at the higher concentrations.

Example 3 Use of Compositions of Volatile Organic Compounds to KillGanoderma boninense in Soil

Since the composition of Example 2 effectively killed Ganodermaboninense, 50 μl of the test mixture of Example 2 (47.5% isobutyricacid, 47.5% methyl ester of isobutyric acid (methyl isobutyrate), and 5%naphthalene) was applied to the base of a 5 ml sterile plastic tubecontaining autoclaved Malaysian sandy loam (from an oil palmplantation). The loam mixture had been inoculated with diced agar blockscontaining a fresh culture of Ganoderma boninense which was equivalentto 0.5 mg dry weight of fungus mycelium. A control tube containing noartificial mixture was also set up. Both were incubated for three daysand then plated on PDA. There was no fungal growth on the treated soil(plate on the right in FIG. 1), but on the control there was enormousgrowth of Ganoderma boninense (plate on the left in FIG. 1). Theconclusion was that the VOC mixture had completely and effectivelykilled all hyphae of Ganoderma boninense that had been placed in thesoil.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that elements of the embodimentsdescribed herein can be combined to make additional embodiments andvarious modifications may be made without departing from the spirit andscope of the invention. Accordingly, other embodiments, alternatives andequivalents are within the scope of the invention and claimed herein.Headings within the application are solely for the convenience of thereader, and do not limit any way the scope of the invention or itsembodiments.

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically canindividually indicated to be incorporated by reference.

What is claimed is:
 1. A method for treating, inhibiting or reducing theincidence of the development of a plant pathogenic disease, wherein saidmethod comprises applying a composition in the vicinity of a host plant,said composition comprising: three or more compounds, wherein the firstof said three or more compounds is isobutyric anhydride; and the secondof said three or more compounds is selected from the group consisting ofone or more of isobutyric acid, methyl isobutyrate, ethyl isobutyrate,propyl isobutyrate, isobutyric acid-allyl ester, and naphthalene, andthe third of said three or more compounds is selected from the groupconsisting of one or more of: caryophyllene and a plant essential oil.2. A method according to claim 1, wherein the second of said three ormore compounds is isobutyric acid.
 3. A method according to claim 2,wherein the third of said three or more compounds is caryophyllene.
 4. Amethod according to claim 2, wherein the composition comprises 20-70%isobutyric anhydride and 20-70% isobutyric acid.
 5. A method accordingto claim 1, wherein the composition comprises 1-10% naphthalene, or1-10% caryophyllene, or 1-10% of a plant essential oil.
 6. A methodaccording to claim 4, wherein the composition further comprises 1-10%caryophyllene.
 7. A method according to claim 1, wherein the compositionfurther comprises an agriculturally effective amount of a pesticidalcompound or composition selected from the group consisting of anacaricide, a bactericide, a fungicide, an insecticide, a microbicide, anematicide, and a food preservative.
 8. A method according to claim 1,wherein the composition is in the form of a powder, a granule, a pellet,a gel, an aqueous suspension, a solution, or an emulsion.
 9. A methodaccording to claim 1, wherein the composition further comprises anagriculturally acceptable carrier.
 10. A method according to claim 9,wherein the carrier is a seed.
 11. A method according to claim 1 whereinthe host plant is a crop plant.
 12. A method according to claim 1,wherein the host plant is an oil palm plant.
 13. A method according toclaim 1, wherein the second of said two or more compounds is selectedfrom the group consisting of isobutyric acid, methyl isobutyrate, ethylisobutyrate, propyl isobutyrate, and isobutyric acid-allyl ester.
 14. Amethod according to claim 1, wherein said plant essential oil isselected from the group consisting of the plant essential oils listed inTable
 3. 15. A method according to claim 4, wherein the compositioncomprises 42-53% isobutyric anhydride and 42-53% isobutyric acid.
 16. Amethod according to claim 15, wherein the composition further comprises3-7% caryophyllene.
 17. A method according to claim 1 wherein the plantessential oil is isocaryophyllene or α-humulene.
 18. A method accordingto claim 1 wherein the composition is applied or coated on a seed.
 19. Amethod according to claim 1, wherein the pathogen is selected from thegroup consisting of Aspergillus fumigatus, Botrytis cinerea, Cerposporabetae, Curvularia sp., Ganoderma boninense, Geotrichum candidum,Mycosphaerella fijiensis, Phytophthora palmivora, Phytophthora ramorum,Pythium ultimum, Rhizoctonia solani, Rhizopus sp., Schizophyllum sp.,Sclerotinia sclerotiorum, Verticillium dahliae, and Xanthomonaaxonopodis.
 20. A method according to claim 1, wherein the compositionis applied in the vicinity of or onto the roots, stems, trunk, seed, orleaves of the host plant.
 21. A method according to claim 1, wherein thecomposition is injected into the roots, stems, trunk, seed, or leaves ofthe host plant.
 22. A method for treating, inhibiting, or reducing theincidence of a plant pathogenic disease, said method comprising exposingor contacting the growth medium of a host plant to or with thecomposition of claim 1 prior to or concurrent with plant growth in saidgrowth medium.